Process of making ortho-oxymonoazo dye.



UNIT D STAT S PATENT .onnien.

AUGUST LEOPOZ'FD LASKA. OF OFFENBACH-ON-THE-IVIAIN. GERMANY, ASSIGNOR'TO OHEMISCHE FARR-IX GRIESHEIM-ELEKTRON, F FRANKFORT-ON-THE-MAIN, GER- MANY, A CORYORATION.

PROCESS OF MAKING ORTHO-OXYMQNOAZO 'DYE.

No Drawing.

To all whom it may concern:

Be it known thatl, Ancusr Lnorou) LASKA, doctor of philosophy, chemist, a sub- :ject of the German l ln'iperor, and resident- 5 of Otlenbach-on-the-\lain, in the Grand Duchy of Hessen, Germany, with the postoflice address Gerbcrstrasse No. 5, havein- -ve'nted new and useful Improvements in Processes of Making ()rtho- Oxymonoazo Dy of which the following is a specification.

I have discovered that a mordaut azo dyestufi of remarkable fastncss can be obtained by combining the ,diazotized nitroamino- '15 salicylic acid (onzeoonmo zan zl214:6

with para-eresol. The thus obtained dye-- stutl' dyes wool from acid bath by subsequent treatment with eliminates yellowishbrown shades of eminent fastness to light. The dyeing process and the treatment with chromates can be carried out in one bath at the same time.

5 The manufacture of the new dyestnfi' may be illustrated by the following example: parts being by weight:

Example: parts of nitroaininosalieylie acid are dissolved in 400 parts of water by means of 35 parts caustic soda lye 35 136., 17.5 parts of sodium nitrite are added, the mix- 85 ture cooled with ice and poured into 114 pa ts of hydrochloric acid 20 Be. cooled with ice. The thus obtained diam compound is poured into a well cooled solution of'32 parts of paracresol in the necessary '40 quantity of caustic soda lye containing an 7 excess of sodium carbonate. The mixture is stirred until the formation of dyestufl' s -eompleted heated up to and the dyestutt' precipitated by addition of common sait.

.45 It is in dry state a brown-black powder, dissolving in concentrated sulfuric acid with Specification of Letters Patent.

Patented Mar. 28, 1911.

Application filed December 13,1910. Serial No. 597,060.

ing the diazotized nitroaminosalicylic acid (01 COOI-LNO: 1 131 1 =2 4; c)

with para-erase].

As a new product. the ortho-oxy-nionoazo dyestult' which is obtained by combining the diazotized nitroaniinosalicylic acid (OHzCOOHzNOgNIL-:12:416)

with para-cresol, which dyestutf is a brownblack powder dissolving in concentrated sulfuric acid with reddish brown. in water with yellowish brown color, which by addition. of caustic soda lye turns more reddish. whereas by addition of concentrated hydrm-liloric a cid the dyesl all is precipitated in form of reddish flakes. which dyesluil' dyes wool from acid bath brownish-yellow shades which, by subsequent treatment. with chromates are turned in y'ellou'ish-bron'n ones of very good fastness to milling and potting and eminent fastness to light.

In testimony, that I claim the foregoing as my invention, I have signed any name in presence of two witnesses, this second day of December 1910.

AUGUST LEOPOLD Lasm.

\Vitnesses Hermann Winn,

Erma MARX. 

